HYDROGEN PRODUCTION FROM ETHANOL STEAM REFORMING IN A SOLID OXIDE FUEL CELL

Abstract

In SOFC, high operative temperature allows the direct conversion of ethanol into H2 to

take place in the electrochemical cell. Direct internal reforming of ethanol, however, can produce

undesirable products that diminish system efficiency and, in the case of carbon deposition over the

anode, massive forces within the electrode structure lead to its rapid breakdown. In this context, a

thermodynamic analysis is fundamental to predict the product distribution as well as the conditions

favorable for carbon to precipitate inside the cell. Hence, the aim of this work is to find appropriate

ranges for operating conditions where carbon deposition in SOFC is not feasible. The effects of

hydrogen consumption on anode components and on carbon formation are investigated.

Equilibrium determinations are performed by the Gibbs energy minimization method. The effect of

the type of solid electrolyte (oxygen-conducting and hydrogen-conducting) on carbon formation is

also investigated. A new approach to model the direct internal steam reforming of ethanol in SOFC

is presented. Theoretical SOFC (oxygen-conducting) efficiencies are accomplished in the region

where carbon formation is thermodynamically impossible. The results of this work are consistent

with previous results from literature.